The present invention relates to a key information processing technology.
Key information has hitherto been utilized in a variety of scenes in the human society. For example, data communications requiring the confidentiality of information involve using encryption keys. Further, what key information is recorded on magnetic stripes is used as a key for a building and an office as a substitute for a metallic key matching with a configuration of a key hole. Pieces of information on encryption keys and keys for the buildings etc are generically termed key information.
The prior art system is, however, incapable of easily changing such a piece of key information and reissuing the key information. Alternatively, even if capable of reissuing the key information, a cipher is required to be stored, and hence the re-issuance needs a re-storing process, which is time-consuming. Therefore, though the encryption keys are used in the communications between information devices such as personal computer (which hereinafter be abbreviated to a PC) and so on, simple communications performed in daily life such as communications between a TV receiver and a wireless remote controller thereof and communications between a wireless keyboard and the personal computer, do not involve the use of the encryption keys.
Supposing that, for instance, home banking through the wireless remote controller and the wireless keyboard will be conducted from now on into the future, however, it is desirable that those communications be performed in an encryption-oriented system. It is because a password etc of a bank account might be intercepted (wiretapped).
It is required that a cipher be agreed upon between communication devices in order for communicating parties to decrypt such a cipher. Accordingly, there is needed a system capable of readily issuing the encryption key with security between the TV receiver and the wireless remote controller and between the PC and the wireless keyboard.
On the other hand, magnetic stripe type and IC card type keys (which will hereinafter be called electronic keys) used for locking and unlocking, e.g., a building, an office and so on, are convenient to carry and therefore easy to be lost and to become a target for theft. These types of keys are managed by, e.g., a center of a key (or building) management company.
Hence, if such a key is lost, all the keys distributed for using the building and offices must be collected, and the key information must be rewritten. The collection and re-issuance of the keys are very time-consuming.